Sliding fifth wheel unit



FIG. 1 is a front, top and side perspective view of the sliding fifth wheel unit embodying the design of the present invention, showing a truck cab and portion of the truck frame in broken lines for illustrative purposes only and forming no part of the claimed design dashed lines;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a side elevational view thereof, the side opposite being a mirror image of the side shown in FIG. 4;

FIG. 5 is a top plan view thereof; and,

FIG. 6 is bottom plan view thereof. 

The ornamental design for a sliding fifth wheel unit, as shown and described. 